— and that’s not necessarily a bad thing
Never Home Alone:
From Microbes to Millipedes, Camel Crickets, and Honey Bees, The Natural History of Where We Live
By Rob Dunn
Basic Books, 325 pages, $37
ISN’T it useful to know some house guests have little respect for home privacy and aren’t impressed by sparkling-clean floors and smudge-free windows?
Since ignorance is bliss only in a fool’s paradise, readers will appreciate some eyebrow-raising discoveries biologist Rob Dunn, a North Carolina State University professor and author of a number of books — including 2008’s Every Living Thing and 2011’s The Wild Life of our Bodies — is willing
“This book is the story of both the life that is likely living beside us in our homes and the way in which that life is changing,” Dunn writes, referring to a wide range of microbial bacteria, fungi, viruses and yeasts — part of some 200,000 life forms sharing our homes with us.
Outnumbering our planet’s wide range of bird and mammal species, these guests inhabit our bodies or attach to our skin, waging unseen wars featuring hordes of harmful microbes (pathogens) arrayed against microbial adversaries which guard our wellbeing.
Fortunately, as Dunn points out, our unseen friends usually far outnumber the fewer than 50 bacterial species which “regularly cause disease.”
Also sharing space in our homes are a host of creepy crawlies in kitchens, bedrooms or basement TV rooms — creatures usually squished or swatted — such as spiders, flies, midges, sow bugs, beetles, ants, wasps, bees and aphids.
Our aversion to this eclectic mix of uninvited, freeloading guests is wellfounded. Some, like cockroaches, mosquitoes and house flies, are known to carry pathogens which cause diseases such as malaria and cholera. But Dunn also presents compelling evidence showing “most of the life in our homes is either benign or good.”
In fact, Never Home Alone is really a robust, scientific defence for both microbial life and for larger creatures too often exterminated simply because they’ve invaded our space.
While data from copious end notes support staid scientific facts from strictly controlled lab tests, an engaging writing style enlivens narratives such as those about microbes in shower heads and beetles on windowsills, transforming Dunn’s latest work into a profound understanding of how all living things help in constructing and maintaining our planet’s complex web of life.
Even more important for our wellbeing, results from controlled experiments prove that some of those cringeworthy pests have the potential to play crucial roles in long-sought scientific breakthroughs.
For example: who knew camel crickets carry bacteria known to be able to degrade industrial waste? What connection can be made between human personality disorders and the proven fact cockroaches’ behaviour is altered by microbial parasites?
Dunn’s intentional profundity is scattered throughout his disclosures, adding to the book’s quirky appeal, especially when paired with one sobering thought: “Every species eventually goes extinct. We will, too.”
Additional grist for the mill comes from challenging the notion that cleanliness is next to godliness. He argues that our obsession with eliminating pathogens and unsightly creatures makes it difficult for friendly microbes to thrive.
Experiments show biodiversity, namely plants, dust, dirt, grime and multi-legged creatures — all carrying microbes — are actually good for us, exposing our bodies to a wide range of microbial life that can evolve into more effective disease-fighting allies.
We desperately need more microbial help, Dunn contends, since surveys from hospitals suggest that indiscriminate use of cleansers and antibiotics not only kills pathogens but also their natural microbial enemies, allowing pathogens free reign to evolve into ever more dangerous strains.
“Bacteria are evolving resistance to our antibiotics faster than we can replace the antibiotics,” he warns, siding with scientists who believe increasing rates of asthma attacks and allergies in humans are the result of living in increasingly sterile environments.
Which guests we should welcome into our homes has suddenly taken on new meaning.